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Google's Project Ara, the so-called
"Lego" smartphone architecture unveiled in April, means intriguing new design
options and opportunity for IP providers in the near term and raises profound
questions for open-source hardware in the long term.
If you missed the buzz, here's
some background: Project Ara, which was initiated at Motorola Mobility, uses
the MIPI Alliance UniPro and M-PHY protocols as the backbone for a modular
electronics architecture inside a smartphone "endoskeleton." Using electro
permanent magnets (they don't need a permanent charge to keep the bond),
designers and consumers can affix various functional modules to build a
customized smartphone--say one with special radios or more powerful imagers or
"Designs will have to be done
modularly to work with the endoskeleton of the phone," said Arif Khan, product
marketing director with Cadence. "Modules will need to play nice with each
other, but if you can get it to work, the ideas and opportunities could be
MIPI UniPro is a multilayer
protocol designed to enable the tunneling of multiple communications protocols
within the system. Layer 1/1.5 include the M-PHY and PHY adapter; Layer 2, the
data link layer for error correction, among other features; Layer 3 includes
ID-based switching; Layer 4 is the transport layer interface to the
UniPro's Unique Opportunity
David Rutledge, chief technologist at Lattice whose FPGAs are being leveraged in the Project Ara Mobile Development Kit, as--among other things--the low-power programmable interface for UniPro, said:
"Project ARA is using (Lattice FPGAs) exactly as intended: high-speed communications of multiple protocols in an extremely low-power device. Ara is a good application of the technology, and it's exactly why UniPro was built. I think this is a major endorsement of the UniPro standard."
Khan said that for
semiconductor makers, Project Ara will be about building chips that will be low
power and work over the endoskeleton using the MIPI M-PHY and UniPro stack to
communicate. At the same time, there is still the challenge of adapting the
UniPort (UniPro + M-PHY) to be used with the adapter/connectors. However, beyond the use of UniPro for just
the UFS and CSI-3 protocols, this is a great statement of the intended use for
UniPro - a unified protocol bus, he added.
"Chip designers will need to
understand the implications of using UniPro for system connectivity," he said. "As
this is not widely used as yet, there will be a learning curve."
Some UniPro resources
Project Ara also raises
intriguing design questions both near and long term.
Expanding IP Opportunity
On the IP front, it likely
means renewed interest in MIPI and other IP, soft and hard, Khan said. If the
module market takes off, the number of design starts will rise, potentially
leading to increased IP consumption. "IP makers will renew their commitment to
the mobile chip space with increased emphasis on low-power designs and
technology," he added.
On the hardware front,
consider the role of either an FPGA or an ASIC as part of the design. Paul
Eremenko, head of Project Ara, who spoke at the developers conference April 15,
described two variants his team examined, one design FPGA-based, the other ASIC-based.
Using the Motorola RAZR MAXX
HD as a baseline, Eremenko showed FPGA and ASICs variants that were larger in
size, weight, and power consumption:
Moto. RAZR MAXX
"Taking that (design) to a
custom variant, with custom ASICs, we can shrink the modularity penalty down to
about a quarter of the size, weight, and power consumption as compared to a
traditional tightly integrated device," Eremenko said.
Lattice's Rutledge, however,
sees plenty of opportunity for makers of small-size, low-power FPGAs since each module contains a
standard interface to the backplane:
"On one side is MIPI UniPro. On the other side is the
module developer's playground. Who knows what they're going to want to do? It's
a perfect place to allow people to innovate. It's an ideal opportunity for
One of the most intriguing
questions surrounding Project Ara is the notion of open hardware architectures,
applied on a broader scale. Open hardware to date has largely been confined to
the "Maker" market through platforms such as Arduino and Raspberry
Khan sees potential but also
"Open hardware implies that there is no phone
maker per se but an endoskeleton maker and module makers. This might seem
interesting, but system compatibility challenges remain. One of the issues in
the Android world is the fragmentation of the OS and customization done to it
by various OEMs."
He added that in an open
hardware platform, engineers are going to have to consider module compatibility
with the other devices throughout system and OS upgrades:
"Anyone who has run into device driver issues
after OS upgrades on a Windows system will know how challenging that is. This
may make the phone brand meaningless per se, but it's more than likely that a
single phone maker may build an endoskeleton and a line of modules that are
optimized to run with it."
The longer term implications
of such an open hardware platform could be significant. Imagine, for example,
the modularity philosophy ported to design in the Internet of Things or
automotive design and so forth.
Lattice's Rutledge said we're
seeing it already. A device teardown may
identify a number of ICs in a given smartphone, but they're really modules, he
"They're pre-built systems in
an SIP that provide dedicated functionality--WiFi, antenna management, or
touchscreen management modules. People don't recognize that," he said.
"The module ecosystem is
developing like the IP ecosystem, and over time different standards will evolve,"
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